I knitted a Klein bottle doorstop, and it's been my intention to knit a Klein purse. I'm a nut for Moebius, and knitted a one-sided bowl with3 Moebius twists in it (it only "looks" like it has two sides). My second sweater, of my own design, is Moebius also.

Thanks flicka, I will have a look for that issue. I have two of the author's books but haven't made anything from them yet, though I have read the chapters on my favorite math subjects. I proposed to knit a Klein bottle hat for DH but he said that it would make him look like a Smurf...